Landing gear protecting boot



June 12, 1945. s, STERGIS 2,373,046

LANDING GEAR PROTECTING BOOT Filed Aug. 9, 1943 INVENTOR. Saws/5A4. 575E615,

, BYVQMDU W ATTORNE Patented June 12, 1945 UNITED STATES PATENT OFFICE.

LANDING GEAR PROTECTING BOOT" Stergis M. -tergis, Los Angeles, Calif. Application August 9, 1943,'Serial No. 497,9' 24 'Claims. (01. 28629) My invention relates to Iandinglgear for air-' craft which is retractable and. extensible through the operation of one or more rams. When the landing gear is. extended and the pistons of the rams are likewise extended, the pistons. are exposed'to the accumulation of sand, dust and dirt, in suchv quantity as to cause the pistons when retracted to jam in the cylinders, and thus prevent them from being extended to lower the landing gear; With the landing gear so locked against operation a belly landing of the aircraft becomes imperative, and the usual disastrousconsequences result.

It is a purpose of my inventionjto provide a protecting coveringfor the ram pistons so that sand, dirt, or any other foreign matter cannot be deposited on the pistons to cause jamming thereof, and thus failure in operation of the landing gear from this cause is eliminated.

It is also a purpose of my invention to provide at protecting covering for a ram piston which is 'inthe'form of aboot so constructed as to be extensible and contractible withprojection and retraction of the piston so as to at all times completely cover and thus effectively protect the wheel or any other part of the landing gear.

I will describe only two forms of protecting boots for the rampistons of landinggear, each embodying my invention and will then point out the novel features thereof in claims.

In the accompanying. drawing:

tinuous ring, l5 made of leather, canvas or any other suitable material, which is both flexible and impervious to sand, dirt, or ani other granular material which may cause the piston and cylinder t jam or become locked against relative linear movement.

As will be clear from an inspection of Fig. 2,

the boot is formed by securing the-inner marginaledges of adjacent rings I5 to each other by stitching IE or many other. suitable manner, and

likewise free axial contraction or collapsing.

Again'as shown in Fig. 2, the terminal rings I5 at opposite ends of the boot body have their outer edges securedto collars l8 and I9, respectively, by stitching 20 or by any other suitable .means. Thes collars are likewise constructed of leather, canvas, or other suitable flexible and impervious material, and are designed for engagement by suitable clamps C and C respectively. to secure the ends of the boot to the cylinder and'pist'on, respectively, of a ram.

' In thepreseni; instance, I have shown clamps of conventional form in that each embodies. a

split band 2| of metal having terminal ears 22 through which a bolt 23 extends for constricting the band and securing the respective collar 1 8 or 9 to the cylinder or piston. i I n 'In Fig. l is shown a simple formof landing gear for aircraft of the retractible type, and wherein a wheel 24 has its axle Z5provided with a'sleeve26 which is securedto the lower end of a piston'2l operating in a cylinder 28 suitably mounted on the aircraft, and adapted to be sup- Fig. l is a view showing in side elevation a simple form of landing gear for aircraft, having applied to th ram thereof one form of boot embodying my invention.

Fig. 2 is an enlarged fragmentary view show ing the boot of Fig. 1, and how his secured to'the ram cylinder. i

Fig. 3 is a View showing in side elevation another form vof boot embodying my invention.

Fig. l i an enlarged plan view of the boot shown in Fig. 3.

Similar reference characters refer to parts in each of the several views. v

Referring specifically to the drawing, and particularlyjto the form of my invention shown in Figs. 1 and 2, the ram piston protecting device comprises a boot; made up of a multiplicity of sections or annuli each in the form of a flat consimilar plied with pressure fluid for extending the piston to lower'the wheel 24, or retracting the piston to elevate the wheel. b r n I The boot of Fig. 2 as applied to the landing gear, employs the clamp C to secure the collar l8 to the sleeve 26', which latter being fixed to the piston 2l moves with the piston. The other end of the boot is secured to the lower end of the cylinder 28 by the clamp C engaging the collar l d.- To' place the boot body in covering relation to the piston it is necessary because of the fact that the boot is an integral unit, to remove the sleeve and wheel from the piston.

With the boot applied to the ram as described. extension of the piston from the cylinder to lower the wheel, causes the boot'body to be elongated or extended to completely cover the piston while extended the piston becomes jammed when drawn back into the cylinder, and thus is prevented subsequent extension of the piston and lowering of the wheel for landing. By maintaining the piston completely covered as is effected by the boot, the surface of the piston cannot become contaminated with sand or other matter, and thus its intended operation is insured.

In the retracted position of the piston the boot, because of its pleated and flexible form readily folds or collapses about the piston so that retraction of the piston is unimpeded by the boot. An important advantage arising from the construction of my boot, is that whether extended or collapsed, it maintains the same internal diameter, and as this diameter is in excess of the diameter of the piston, the boot at no time contacts the piston to remove lubricant therefrom or interfere with it movement.

Referring now to Figs. 3 and 4, I have here shown another form of protecting boot which is characterized by being divided or split lengthwise so that it can be applied to the piston and cylinder without the necessity of removing any part of the landing gear.

In this form of boot each section of the tubular boot body is likewise in the form of a flat ring of leather or other flexible and impervious material, but each ring is formed of two arcuate parts 29 and 30, with each part in excess of a semicircle. One of the ends of the two parts are secured in abutting relation ,to each other by stitching 3|, and as each part is in excess of a semi-circle the other ends 32 thereof are disposed in overlapped relation to each other, and thus the internal contour of the section is that of a circle.

.The several sections comprising the tubular body of this form of boot are secured one to the other in the same manner as those of the first form of boot described herein, so that the body is circumferentially pleated and thus extensible and foldable in a like manner. Also, the ends of the boot body are likewise provided with collars 33 and 34' made of the same material as the body sections, but each collar is split and of a diameter such that when secured by stitching 35 at its inner edge to the outer edge of the adjacent body section, its overlapped ends are transversely alined with the overlapped ends of the body'sections. Thus the boot is divided or split from end to end so that it can be opened and placed about the cylinder and the piston without disturbing any part of the landing gear.

To secure the divided boot in tubular form.

about the parts of the ram, any suitable means which'is flexible so as not to interferewith extension and collapse of the boot, may be employed. In this instance I use a single length of cord 36 which is trained through suitable perforations in the overlapped ends'of the sections and collars, and then tied so as to secure the overlapped ends against separation.

As in the first form of boot, the same clamps C and C may be employed to secure the collars 33 and 34 tightly about the cylinder and piston sleeve so that the boot body collapses and expands with extension and retraction of the piston, and thus at all times covers and protects the piston against contamination by sand and other granular matter.

Although I have herein shown and described only two forms of protecting boots for aircraft landing gear, each embodying my invention, it is to be understood that various changes and modifications may be made herein without departing from the spirit of my invention and the spirit and scope of the appended claims.

I claim:

1. A protecting boot of the character described, comprising, a plurality of fiat annuli of flexible and impervious material, each annulus being formed of two arcuate sections secured permanently to each other at one of their confronting ends in abutting relation, while their other ends are disposed in overlapped relation, and adjacent annuli being secured at their outer edges to each other and at their inner edges to each other, whereby a circumferentially pleated and tubular bod is formed; split collars secured to the ends of said body and having their ends overlapped at a point corresponding to the overlapped ends of said annuli; and means engageable with the overlapped ends of said annuli and said collars for detachably securing said body and said collars in circular form.

2. A protecting boot for the rams of retractible landing gear for aircraft, comprising a tubular body permanently pleated ciroumferentially so that it is axially extensible and contractible, and divided lengthwise from end to end with the edges of the divisions overlapping each other circumferentially; and .means extending through said overlapped edges and longitudinally of said body for securing said body in tubular form, said means being flexible to allow complete contraction in pleated form of said body, and detachable from said edges to allow opening of the body for de tachment from a ram. l

3. A protecting boot for'the rams of retractible landing gear for aircraft, comprising a tubular body permanently pleated circumferentially' so that it is axially extensible and contractible, and divided lengthwise from end to end with the edges of the divisions overlapping each other; and a single lace extending through said overlapped edges for securing said body in tubular form.

4. A protecting boot of the character described, comprising a plurality of fiat annuli of impervious material, means for securing the confronting outer edges of adjacent annuli to each other and the inner edges of adjacent elements to each other to form a tubular body of, permanently pleated form circumferentially, each annulus formed of two arcuate sections secured permanently to each other at one of their confronting ends, while their other ends are disposed in overlapped relation; said material and said securing means being of flexible material; and a lace extended through said overlapped ends for detachably securing said body in tubular form.

5. A protecting boot of the character described, comprising a plurality of flat annuli of impervious material, means for securing the confronting outer edges of adjacent annuli to each other and the inner edges of adjacent elements to each other to form a tubular body of permanently pleated form circumferentially, each annulus formed of two arcuate sections secured permanently to each other at one of their confronting ends by stitching, while their other ends are disposed in overlapped relation; said material and said securing means being of flexible material; and means engageable with the overlapped ends of said annuli for detachably securing said body in tubular form, said means being flexible to allow complete axial collapsing of said body while maintaining its circumferentially pleated form.

STERGIS M. STERGISf 

